Is it just me, or was this a difficult theme to get right? Numbers are easy to implement, but making them a key theme was difficult, at least for me.
I understand what you mean - numbers are a tool used to represent things, so many aspects of a game can be replaced by them. In my opinion, taking a game idea and replacing some of its components with numeric representations (for example, replacing blocks with a number indicating their height) or simply numbering game elements just doesn't quite hit the theme. That's probably what made it much harder (personally, also my perfectionism)
That's why I chose to make a game that uses numbers as a main element of a puzzle. However, later I found a way to remake my game without the use of numbers... ¯\_(ツ)_/¯
I can understand why the week's theme has fewer submissions. Maths puts many people off, and finding the fun in numbers can be challenging. Some of my feedback was that the equations I had chosen, "x+y*z=N", were too hard, yet in my head, I was thinking about equations like "x+ y + z*z = N". I think the other issue was that them numbers are very symbolic; different themes are more imaginary or emotional to them.